fix: always advance last_svn_revision even when no new revs (already mapped)

svn_mirror/sync.py

@@ -450,8 +450,7 @@ def _sync_all_impl(mirror: Mirror) -> int:
             logger.exception("Failed to sync SVN r%d for %s", rev, mirror.config.id)
             raise
 
-    if count:
-        mirror.db.set_state("last_svn_revision", str(latest_rev))
+    mirror.db.set_state("last_svn_revision", str(latest_rev))
     logger.info("Synced %d revision(s) for %s", count, mirror.config.id)
     return count